I.V. sets are well-known in the art for delivering intravenous fluid to a patient by means of a needle connected through a winged body. They are designed to be temporarily installed to deliver fluid directly to the patient's vein through the extended needle. The wings are used to handle the assembly during insertion and withdrawal and to stabilize the device. The wings provide a broad contact area which allows taping the device to the patient while discouraging movement, especially any rotation, of the device.
A problem occurs upon withdrawal because the needle, now contaminated with blood or other body fluid, must be disposed of without risking needle sticks to medical personnel engaged in the operation of withdrawing the winged I.V. set or to hospital disposal personnel. Caps or covers that are mounted over the needle are not a satisfactory solution because someone must put them in place and because they can become loose and expose a used needle.
U.S. Pat. No. 5,088,932 to Ryan for Safety Winged Needle Medical Devices discloses a double wing IV set in which a slidable hollow winged shield is used to cover a removed needle. One set of wings is attached to a hollow winged shield and one set of wings to a hollow inner tube encircled in part by the hollow winged shield. During use, the shield is frictionally engaged over one end of the inner tube which carries the needle on its other end. When finished, the needle is covered by separately gripping the sets of wings to move the shield forward relative to the inner tube until the shield is locked into position covering the needle.
U.S. Pat. No. 5,120,320 to Fayngold for IV Infusion or Blood Collection Assembly w/Automatic Safety Feature discloses a single wing IV set which uses a separate slidable two-part shield to cover a removed needle/tube assembly. The shield may be opened and positioned around the needle/tube assembly rather than requiring a threading process. Once in place, the needle is covered by pulling the assembly back through the shield which uses guide grooves for the wings to control orientation and to deliver the wings over a ledge into a rear slot which locks the system in its covered position.
U.S. Pat. No. 5,330,438 to Gollobin et al. for Protective Sheath for Butterfly Needles and IV Intusion Set and Sheath Assembly and U.S. Pat. No. 5,192,275 to Burns for IV infusion or Blood Collection Guard Assembly both disclose single wing IV sets which use slidable protective sheaths to cover removed needle/tube assemblies. The sheaths are manually slid over the assembly to cover the needle. Gollobin locks the sheath in the covered position by capturing the wings in a fashion si ar to Payngold (above), while Burns'cover has grooves to allow the wings to travel past but does not appear to positively interact with the wings. The cover in Burns is locked in the extended position by locking lugs on the housing which drop off a ledge into indentations or slots.
U.S. Pat. No. 5,409,461 to Steinman for Catheter Introducer Assembly with Needle Shielding Device discloses a winged catheter introducer in which a needle is used to introduce an IV tube into the patient, and then drawn back manually through the tube and into a holding container for safe storage, leaving a catheter in place to provide fluid communication between the patient and the IV. The wings are not involved in the retraction of the needle.
Prior art safety systems for winged I.V. sets are seen to be problematic. Most of the prior art safety winged I.V. sets rely on manual sliding of a cover over the needle. They almost always involve the need for two handed operation and may not be operated until after the needle is removed and clear of the patient. Some of the systems must be threaded into pre-existing winged I.V. sets creating additional difficulties for healthcare workers prior to insertion of the needle. They also open the possibility for additional error if improperly put in place. Almost all of the systems require healthcare workers to put their hands around and near the exposed needle in order to slide the cover or sheath into place around it. These problems are reduced or eliminated by the present invention.
Additionally, it is important that winged I.V. sets be easily molded on production equipment in large quantities and have few parts. Assembly is equally important because the devices are mass produced and preferably assembled with the aid of machines. The present invention is a significant improvement over the prior art which allows safe, one-handed controlled retraction of the needle directly from the patient without removing the device from its pre-retracted position. The present invention is economical to mass produce and assemble at low cost. The housing can be molded in one piece. The only other part is the retraction body, except for the needle and retraction spring. The present invention offers a significant improvement over the prior art devices and accomplishes all of these objects and more.